Shelley opens with a door swinging inward: "The golden gates of Sleep unbar." What waits behind it is a couple rather than a dream, "Strength and Beauty, met together." Neither bride nor groom is named, and the title makes that unnecessary. The capital letters turn two people into qualities, so the wedding becomes a meeting of ideals. Their union "kindle[s] their image like a star / In a sea of glassy weather," a picture of reflection, one bright point doubled in perfectly still water. The word "glassy" promises calm before anything has happened.
The poem is essentially a series of appeals for protection. The speaker calls on Night, Darkness, the stars, the Hour, "fairies, sprites, and angels," and finally Dawn. Each is given a job. Night must "look down," Darkness must "weep thy holiest dew," and the spirits must "keep her." Even the moon gets a compliment at its own expense: it is "inconstant," always changing, and has "never smiled" on a pair so "true." Constancy is set against the changeable sky, and the lovers come out as steadier than the heavens. Darkness, usually a threat in poetry, becomes a curtain and a guard.
The sound of the poem shapes this mood. Lines are short, mostly four stresses or fewer, and the rhythm moves between a light iambic step ("The golden gates of Sleep unbar") and a falling, trochaic one ("Never smiled the inconstant moon"). That falling beat gives the commands a hushed, chant-like quality, like a blessing. The first stanza begins with tidy alternating rhymes, *unbar/star* and *together/weather*, the second pair soft and two-syllabled. Then *dew*, *true* and, much later, *renew* tie the stanza together across its length, while *down* and *moon* match only loosely, as if the stanza were relaxing its grip. The lines also shrink toward the end: "On a pair so true" is only five syllables, and "Oft renew" is two. The stanza dwindles away like a lowered voice.
The most interesting tension is in the middle. "Let eyes not see their own delight" is open to more than one reading. It might ask for privacy from watchers, or it might suggest joy so great it cannot look at itself. Either way, the next lines send time hurrying ("Haste, swift Hour"). The speaker wants the night guarded and also wants it to pass, and the second stanza makes that contradiction explicit. The stanza is shorter and quicker, with the rhymes *wrong*, *long* and *along* ringing through it. It asks the stars to "permit no wrong" and Dawn to return "ere it be long." Then comes the poem's most human moment: "O joy! O fear! what will be done / In the absence of the sun!" The exclamations break the formal blessing. Underneath the fairies and angels is a nervous onlooker who cannot decide whether to be thrilled or anxious. The vagueness of "what will be done" is both discreet and slightly teasing, since it avoids saying anything while making sure we understand.
The closing "Come along!" fits the poem's shape well. It rhymes with *wrong* and *long*, so it feels like the answer to those wishes, and it is a bare, brisk command. It could be addressed to Dawn or to the hurrying Hour, and that uncertainty keeps the ending light on its feet. After so much solemn invocation, the poem finishes almost with a grin.
The poem's significance lies in what it does with a very small space. Shelley, a major Romantic poet, makes a wedding night a matter for the whole sky without losing the human feelings at its centre. The stars, moon and dawn are made to listen, which is typical of the way Romantic poetry treats nature as responsive to human experience. In under twenty lines he moves from calm reflection to anxious excitement, and the shortening lines and growing rhyme help carry that change. It shows that a poem of occasion can be tender, a little comic and carefully built all at once.